junk in the trunk

Apparently, Chicagoans have big butts. So big, in fact, that the CTA needs new, bigger bus seats to accomodate them. What I want to know is this: if the seats are currently 17 1/2", are the new 18" seats really going to make that much of a difference? As in, "whoa, I was totally squished before and avoided sitting down at all on buses because I was unable to stand up again once I had wedged myself down in there, but now with the extra half inch things are nice and comfy?" Really?